Orthtic device and method for providing static and dynamic stability to the medial arch and subtalar bone complex

ABSTRACT

Orthotic devices are configured to provide static and dynamic stability to the medial arch and subtalar bone complex. The orthotic device includes a resilient arch support configured to collapse under the weight of a user. Collapsing causes an operably coupled vertical support flange to pivotally urge the vertical support flange against corresponding medial areas of the foot. A method entails translating a downward force exerted by a foot during walking motion into pivotal motion of the vertical support flange. Pivotal motion urges the flange against corresponding areas of the foot to providing a stabilizing force. As the downward force is relieved, the stabilizing force is relieved and the medial support flange returns to its original position.

RELATED APPLICATION

This application claims the benefit of priority of U.S. provisional application 60/868,079, filed Nov. 30, 2006, the entire contents of which are incorporated herein by this reference.

FIELD OF THE INVENTION

This invention generally relates to orthopedic devices adapted to relieve or correct foot problems, and, more particularly, to an orthotic configured to provide static and dynamic stability to the medial arch and subtalar bone complex.

BACKGROUND

The mechanical features of the human foot are produced by the organization and function of its bones, joints, muscles, ligaments and tendons. The interaction of these anatomical components determines the efficacy of the foot in both the static and dynamic modes. When in the static mode, the foot acts as a load bearing structure designed to comfortably tolerate the forces associated with standing or sitting. In the static mode, while sitting, lying, or standing, the foot is at rest and the overall structure and shape of the foot is maintained through passive stabilizers i.e., ligamentous structures that are able to maintain the arches of the foot without assistance from muscles. In the dynamic mode, the foot alternates functions as a propulsive rigid lever from which to walk jump or run, and mobile adaptor upon which uneven terrain can be navigated. In the dynamic mode, while walking, running, or any activity involving greater forces than static forces on the foot, the general structure of the foot is maintained by both static and active stabilizers. Active stabilizers are muscles of the foot or lower leg that aid in the stabilization of the foot.

Optimal functionality of the foot requires that its anatomical mechanisms operate effectively. A common dysfunction of the foot is excessive rotary motion known as pronation, which is a multi-factorial dysfunction, not attributable to any single underlying cause. When in the static mode, excessive pronation presents merely as a lowering of the inside arch of the foot. Currently available orthotics simply address the appearance of the fallen arch with a shoe insert that forms a prominence that exerts a force on the fallen arch in an attempt to push it up. These orthotic devices are ineffective for most people because the appearance of the fallen arch is only one aspect of the dysfunction. In addition, excessive pronation, and a myriad of accompanying mechanical insufficiencies occur in the dynamic mode of the foot. Currently available orthotic inserts do not address the dynamic mode excessive pronation, nor do they address the other associated mechanical insufficiencies of the foot during this mode.

The skeletal structure of the foot can be described along the coronal (side to side) plane by three regions: rear-foot, mid-foot, and fore-foot. The rear-foot region is the area of the heel bone (calcaneus) and the ankle bone (talus). These bones are the largest of the foot and are responsible for bearing the greatest forces. The talus articulates with the long bones of the leg, the tibia and fibula, to form the ankle joint. The talus also articulates with the calcaneus to form the subtalar joint. The calcaneus provides an attachment point (calcaneal tuberosity) for the tendons (Achilles tendon) of the large muscles of the lower leg that are responsible for the dorsiflexion (foot pointing up) and plantar flexion (foot pointing down) movements of the foot. The mid-foot consist of a complex of bones that articulate with the rear-foot complex and the fore-foot complex. The organization of the mid-foot complex is such that the large forces experienced at the rear-foot complex are transmitted along the outside (lateral) portion of the foot and distributed along and across the inside (medial portion) of the foot. The lateral mid-foot complex comprises the cuboid and fourth and fifth metatarsal bones. The cuboid articulates with the calcaneus closest to the ankle (proximally) and with the fourth and fifth metatarsals farthest away from the ankle (distally). The medial portion of the mid-foot complex is composed of the navicular; medial, intermediate, and lateral cuneiforms; and the first, second, and third metatarsal bones. The proximal articulation of the navicular is with the talus. The distal articulation of the navicular is with the medial, intermediate and lateral cuneiform bones. The distal articulation of the three cuneiform bones is with the proximal head of the first, second and third metatarsal bones. The fore-foot region encompasses all of the bones forward of the distal head of the metatarsals. These bones are the phalanges, of which there are two along the axis of the first metatarsal, and three each along the second, third, fourth and fifth metatarsals.

This arrangement creates two arches, a longitudinal arch in the sagittal plane, and a transverse arch in the transverse plane. The medial portion of the longitudinal arch is the highest arch, which decreases laterally to the low lateral arch. In combination, these plantar arches enable the foot to adapt to varying terrain by displacing compressive forces throughout the structure of the foot, and allow the foot to act as a shock absorber.

During both the static and dynamic modes of the foot, the motion of the bones about the joints with adjacent bones (articulation) is limited by tensile forces developed in the ligaments that intersect the articulating bones. Ligaments are semi-elastic, mechanically strong fibrous structures that transverse joints and maintain the alignment of bones. In combination, the action of all of the ligaments of the foot maintain the overall static arch structure of the foot and help to realign the structure of the foot during the dynamic mode. The passive stabilizers of the longitudinal arch are the plantar aponeurosis, the long plantar ligament, and the plantar calcaneonavicular (spring) ligament. The plantar aponeurosis is the longest, and therefore most important passive stabilizer. It intersects the plantar aspect of the calcaneus and extends to the distal portion of the metatarsals and proximal portion of the proximal phalanges. As a passive stabilizer in the static mode, the plantar aponeurosis provides a constraining force that maintains the longitudinal arch curvature. In addition, as a passive stabilizer in the dynamic mode, it provides a windlass effect that restores the longitudinal arch during walking. Similarly, the long plantar ligament extends from the distal portion of the calcaneus and intersects the cuneiform bones. The long plantar ligament is a shorter ligament and therefore represents a less effective passive stabilizer because of the lower constraining force it applies to the longitudinal arch. Lastly, the plantar calcaneonavicular is the shortest and least effective passive stabilizer. This spring ligament offers the only direct connection between the navicular and calcaneus, intersecting the medial and plantar aspects of the navicular and the sustentaculum tali. Ligaments that have been over stretched lose their elastic properties (ligamentous laxity) and become incompetent. This incompetence can cause misalignment of the bones that are supported by the ligaments.

Bones articulate about joints by the application of force applied to the bone at a tendon intersection. Tendons consist of cartilage cells and collagen fibres and provide a flexible attachment of muscle to bone. As a muscle contracts, it shortens providing a force along the length of the tendon resulting in an articulation of the bone in the direction of the tendon. In addition to the tensile forces developed in ligaments, bone articulation is limited by opposing (antagonistic) forces applied by other muscle tendons attached to opposite locations of the articulating bone. During the dynamic mode, active stabilizers increase the mobile adaptor function or increase the rigid lever function of the foot. The flexor hallucis longus (FHL), flexor digitorum longus (FDL) and the posterior tibial tendon (PTT) are the long tendons responsible for the active stabilization during dynamic mode of the foot. The most important dynamic stabilizer is the PTT. The PTT has multiple insertion sites on the medial-plantar aspect of the foot. The main insertion is on the plantar aspect of the navicular, with lesser insertions onto the cuneiform and metatarsal bones. During dynamic mode the PTT, by contraction of the posterior tibialis muscle, creates subtalar inversion and locks both the calcaneocuboid and talonavicular joints, thereby creating a rigid lever for the propulsive phase of gait. In addition, the PTT acts as a stabilizer during the static mode of the foot. As with ligaments, overstretching of tendons may cause inelasticity and incompetence of the tendon.

Human gate comprises two distinct coordinated phases of motion that together start and end with the heel strike of the same foot (i.e., ipsilateral heel strike). The stance phase is the period of time during which the foot is in contact with the ground. The swing phase is the period of time in which the foot is off the ground and swinging forward. During the contact portion of the stance phase the foot is pronating at the subtalar joint. Pronation generally involves a depression of the arch, mobility of the foot and an internal rotation of the leg. During pronation, the sole of the foot is turned outward so that the inner edge of the foot bears the weight when standing. The leg is internally rotating and the foot is absorbing shock and functioning as a mobile adaptor to the ground surface. The next portion of the stance phase is called midstance. Midstance begins when the entire foot has contacted the ground. The body weight passes over the foot as the tibia and the rest of the body are moving forward. The opposite foot is off the ground and the grounded foot is bearing the entire body weight. During this portion of the stance phase, the leg is externally rotating and the foot is supinating at the subtalar joint. In a supinated position, the foot is turned or rotated by adduction and inversion so that the outer edge of the sole bears the body's weight. Supination generally involves an elevation of the arch and stability of the foot structure with external rotation of the leg. The foot transforms from being a mobile adaptor to becoming a rigid lever in order to propel the body forward during the final portion of the stance phase—propulsion.

Propulsion begins after heel off and ends with toe off. The body is propelled forward during this phase, while weight is shifted to the opposite foot as it makes ground contact. The subtalar joint must be in a supinated position in order for this phase to be normal and efficient. If abnormal pronation occurs, the midstance phase and this phase will probably be prolonged and weight transfer through the forefoot will not be normal.

The swing phase begins immediately after toe off. The first portion of the swing phase is the forward swing which occurs as the foot is being carried forward. The knee is flexed and the foot is dorsiflexed at this time. The next segment of the swing phase is foot descent as the foot is being positioned in preparation for weight bearing and the muscles are stabilizing the body to absorb the shock of heel contact. At heel contact, the swing phase ends and a new gait cycle begins.

As the foot contacts the ground, it must be flexible so that it can adapt to a variety of surfaces. Upon contact, the foot begins to roll medially at the subtalar joint, and the medial arch lowers. This pronation movement accommodates variable ground surfaces and helps absorb the shock of the entire body weight. If the normally elastic plantar aponeurosis, plantar long ligament and spring ligament have undergone plastic deformation, they will no longer spring back and realign the bones of the mid foot complex, and the foot stays pronated. As a result of this excessive and prolonged pronation, the posterior tibial tendon is unable to lock the bones of the mid-foot to create a rigid lever for toe off creating excessive forces on the PTT. Over time there is a gradual attenuation of the medial static constraints of the longitudinal arch mechanism and the foot losses its mechanical advantage during gate. Repeated excessive forces on the PTT cause eventual incompetence of the PTT and result in hyperpronation. Abnormal pronation accentuates the rotational forces that are transmitted through the foot.

Pronation and supination problems require varying support for various parts of the foot, including support for the bones of the rear-foot and mid foot complex (i.e., subtalar complex), statically and dynamically through the gait cycle. Unfortunately, however, conventional orthopedic corrective devices suffer shortcomings, as none provide an orthotic specifically adapted to provide improved stability of the foot structure during the static and dynamic modes of the foot. Specifically, no known prior art orthotics provide a dynamically adjusting structure that exerts lateral corrective pressure.

Accordingly, a need exists for a method and orthotic configured to provide static and dynamic stability to the medial arch and subtalar bone complex. The invention is directed to overcoming one or more of the problems and solving one or more of the needs as set forth above.

SUMMARY OF THE INVENTION

In one aspect of an exemplary embodiment of the invention, an orthotic device for a foot is configured to provide static and dynamic stability. The device includes a base, a dynamic vertical support flange coupled to the base and configured to controllably pivot and apply pressure against corresponding medial areas of the foot, and a means for controllably causing the dynamic vertical support flange to pivot. The means for controllably causing the dynamic vertical support flange to pivot includes any means for translating a downward force exerted by a foot during walking motion into pivotal motion of a medial support flange. By way of example a cantilever arch support may be pivotally coupled to the base and configured to pivot downwardly upon application of a downward force. The dynamic vertical support flange may be operably coupled to the cantilever arch support and configured to pivot and apply pressure against corresponding medial areas of the foot when the cantilever arch support pivots downwardly. Specifically, the dynamic vertical support flange coupled to the cantilever arch support may be configured to pivot and apply pressure against a medial arch and subtalar bone complex of the foot, e.g., medial cuneiform, navicular and talar bone structures. The cantilever arch support may include an arch support pad configured to cushion an arch of the foot. The pad may be removably or permanently attached to the arch support, such as in a correspondingly sized and shaped recess.

In another aspect of an exemplary embodiment of the invention, a heel cup may be permanently or releasably attached to the base and configured to support a heel of the foot. In an exemplary embodiment, an integral heel cup tongue protrudes rearwardly from the base. The heel cup has a cavity configured to receive and engage the heel cup tongue. The heel cup tongue may also include a locking protuberance, in which case the heel cup may have a means for engaging the locking protuberance. To accommodate various foot sizes, the heel cup may be sized to cause the orthotic to fit. Additional attachments may include at least one female receptacle in the base and at least one male prong configured extending from the heel cup and configured to engage the at least one female receptacle and operably couple the heel cup to the base.

In another aspect of an exemplary embodiment of the invention, an integrally molded orthotic device for a foot is configured to provide static and dynamic stability. The device includes a base, a dynamic vertical support flange coupled to the base and configured to controllably pivot and apply pressure against corresponding medial areas of the foot, and a cantilever arch support pivotally coupled to the base and configured to pivot downwardly upon application of a downward force, the dynamic vertical support flange may be operably coupled to the cantilever arch support and configured to pivot and apply pressure against corresponding medial areas of the foot when the cantilever arch support pivots downwardly. Means for attaching an arch support pad configured to cushion an arch of the foot may be provided. Additionally, means for attaching a heel cup configured to cushion a heel of the foot may also be provided.

In another aspect of an exemplary embodiment of the invention, a method of stabilizing a medial arch and subtalar bone complex is provided. The method includes steps of translating a downward force exerted by a foot during walking motion into pivotal motion of a medial support flange, urging the medial support flange against corresponding areas of the foot to provide a stabilizing force, relieving the downward force; and relieving the stabilizing force as the downward force is relieved.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other aspects, objects, features and advantages of the invention will become better understood with reference to the following description, appended claims, and accompanying drawings, where:

FIG. 1 is a lateral view of an exemplary right foot skeletal system for conceptually illustrating principles of the invention; and

FIG. 2 is a medial view of an exemplary right foot skeletal system for conceptually illustrating principles of the invention; and

FIG. 3 is a dorsal view of an exemplary right foot skeletal system for conceptually illustrating principles of the invention; and

FIG. 4 is a top perspective view of an exemplary orthotic device in accordance with principles of the invention; and

FIG. 5 is a lateral side perspective view of an exemplary orthotic device in accordance with principles of the invention; and

FIG. 6 is a front side perspective view of an exemplary orthotic device in accordance with principles of the invention; and

FIG. 7 is a rear side perspective view of an exemplary orthotic device with a removed arch cushion and heel cup in accordance with principles of the invention; and

FIG. 7A is a bottom cutaway perspective view of an exemplary heel tongue portion for engaging a heel cup of an exemplary orthotic device in accordance with principles of the invention; and

FIG. 8 is a bottom perspective view of an exemplary heel cup for use with an exemplary orthotic device in accordance with principles of the invention; and

FIG. 9 is a top perspective view of an exemplary arch cushion for use with an exemplary orthotic device in accordance with principles of the invention; and

FIG. 10 is a lateral side view of another exemplary orthotic device in accordance with principles of the invention shown in operative alignment with bones of a right foot; and

FIG. 11 is a first schematic of a dynamic model to conceptually illustrate principles of the invention; and

FIG. 12 is a second schematic of a dynamic model to conceptually illustrate principles of the invention.

Those skilled in the art will appreciate that the invention is not limited to the exemplary embodiments depicted in the figures or the shapes, relative sizes, proportions or materials shown in the figures.

DETAILED DESCRIPTION

With reference to FIGS. 1-3, there is shown a typical human foot 100, and (in FIGS. 1 and 2) the tibia 105 and fibula 110, the two lower bones of the leg. Below the tibia 105 and fibula 110, there is the talus 110 (i.e., the “ankle bone”). Positioned below and rearwardly of the talus 110 is the calcaneus 115 (i.e., the heel bone). Positioned moderately below and forward of the talus 110 are the navicular 120 and the cuboid 125. Extending forwardly from the navicular 120 are three cuneiform bones 140. Extending forwardly from the cuneiform bones 140 and from the cuboid 125 are the five metatarsals 130. Forwardly of the metatarsals 130 are the phalanges 135.

An exemplary orthotic device according to principles of the invention provides static and dynamic stability to the medial arch by decreasing the effective vertical force applied to the plantar fascia, allowing it to function optimally, while providing dynamic horizontal stability to the subtalar bone complex during gate. Both static and dynamic stabilization is achieved using a vertical adjustable support structure of the orthotic device, which is adapted to provide a stabilizing force to targeted regions of the subtalar bone complex.

Referring to FIGS. 4 through 6, top, lateral and front perspective views of an exemplary orthotic device 400 according to principles of the invention are conceptually shown. The device includes a base 410 with a heel cup 420, a substantially planar lateral support surface 490 and a substantially planar phalanges support surface 405. Lateral joints 430, 450 and 455, 435 define front and rear pivot points about which the vertical support flange 490 pivots. The exemplary vertical support flange 490 includes cuneiform support 470, navicular support 425 and talar support 475 sections. The exemplary vertical support flange 490 is integrally attached to an arcuate resilient arch support 460.

A shallow pocket 720 (as shown in FIGS. 7 and 9) defined within the arch support 460 receives and holds an arch support pad 465 which is thicker than the pocket depth. The pad 465, which may be comprised of any suitable cushioning and/or supportive material, thus provides cushioned support to an arch. The pad may optionally be removably attached using adhesive, hook and loop fasteners or mechanical attachments. A rigid, semi-rigid or cushioned heel cup 420 is provided. The heel cup depth may vary from shallow (e.g., 10 mm or less) to deep (e.g., 18 mm or more)—the deeper the heel cup, the greater the control of the heel.

Likewise, the heel cup 420 may be removably attached. By way of illustration and not limitation, in an exemplary embodiment the orthotic 400 includes a rearward tongue 715 or tenon, configured to fit snugly within a groove or mortise in the heel cup 420, as shown in FIGS. 7 and 8. In a preferred embodiment, the rear of the orthotic 400 includes a pair of female receptacles 705, 710, configured to securely engage a corresponding pair of male prongs 810, 815 on the heel cup. The exemplary heel cup 420 also includes an aperture 820 to allow air to escape during installation and to engage a corresponding protuberance 725 on the bottom of the tongue 715, as shown in FIG. 7A, for locking engagement. The exemplary heel cup 420, which may be comprised of any suitable cushioning and/or supportive material, thus provides comfort and support to the heel of a user.

Advantageously, the removable heel cup 420 facilitates sizing. A heel cup 420 may be selected to fit a particular foot. Thus, a relatively long heel cup 420 may be selected for a long foot, while a small heel cup 420 may be selected for a small cup. Using the replaceable heel cup 420, the exemplary orthotic 100 may be configured to fit a wide range of feet sizes. This greatly facilitates both manufacturing and maintaining inventory.

Concomitantly, the removable heel cup 420 facilitates customization for particular needs and activities. For example, a user may want a softer or firmer, thicker or thinner, wider or narrower heel cup during certain activities and with certain footwear. Interchangeable heel cups 420 of varied firmness and/or dimensions may be used.

The orthotic includes a means for translating downward force to lateral movement of the vertical support flange 490. By way of example and not limitation, as a downward force is applied to the arch support 460 of the exemplary embodiment, such as during walking and standing, the arch support pivots downwardly as shown by the arrows 485 in FIG. 4 and the vertical support flange 490 pivots laterally, i.e. towards the foot, as shown by the arrows 480 in FIG. 4. The lateral movement of the vertical support flange 490 provides lateral support. The vertical support flange 490 may be shaped and dimensioned to direct the lateral pressure to the areas of the foot that will benefit most from the lateral support, as conceptually illustrated in FIG. 10. As the downward force is relieved, because the joints 430, 450 and 435, 455 are resilient, the arch support 460 and vertical support flange 490 return to their un-deformed position.

In the exemplary embodiment depicted in the Figures, the pivot axis is defined by the pivot joints 430, 450 and 435, 455. Those skilled in the art will appreciate that other means for defining a pivot axis, such as an axle, hinge or the like, may be utilized. Likewise, means other than resilient joints may be used to urge the arch support 460 and vertical support flange 490 return to their un-deformed positions. By way of example and not limitation, such means may include torsion bars, springs, and compressible structures such as foams, sponges and bladders.

The vertical support flange 490 may be cushioned for comfort, fit and effectiveness. A removable cushioning sleeve and/or cushion overmolding may be applied to the vertical support flange 490.

Referring now to FIGS. 11 and 12, schematics of a dynamic model to conceptually illustrate principles of the invention are provided. In use, the exemplary orthotic device 400 is placed in the upper of a shoe or other footwear. A user's foot is placed in the upper on the orthotic device 400, with the sole of the foot against the base 410, the heel of the foot in the heel cup 420 and the medial side of the foot against the vertical support flange 490. The arch support 460 is configured to yield to a downward force F from the weight of a body applied to the foot during walking motion. Under the applied force, the arcuate arch support 460 is urged downwardly. This downward motion causes the integrally attached vertical support flange 490 to pivot an angle θ about the axis defined by the pivot joints 430, 450 and 435, 455. The pivotal movement of the vertical support flange 490 urges the cuneiform support 470, navicular support 425 and talar support 475 sections against corresponding areas of the foot, thereby providing stabilizing forces that help maintain the targeted portions of the foot in proper configuration and orientation. Advantageously, the invention translates downward deflection of the arch support 460 to lateral support for stabilizing the cuneiform, navicular and talus areas of the foot. Upon relieving the downward force F, the arch support 460 returns to its original configuration.

Referring again to FIG. 10, the talar support structure 475 applies a mediolateral force to an area of the plantar calcaneonavicular ligament (i.e., spring ligament) to augment its function. The spring ligament is a passive stabilizer that intersects the plantar and medial portions of the navicular tuberosity and intersects the sustenta-culum tali of the calcaneus, and partially covers the naviculo-talar articulation. The spring ligament inhibits medial and plantar displacement of the navicular and talus. The mediolateral force supplied by the exemplary orthotic device to the spring ligament region provides static stabilization through the complete range of vertical forces applied to the foot. As vertical force is applied to the foot, the mediolateral force supplied by the exemplary orthotic device increases and resists the medial horizontal component of pronation, thereby inhibiting both axial rotation of the calcaneus and torsion of the lower leg.

A plantar deforming arch support 460 resists the plantar-vertical component of pronation by applying a dorsi-vertical force to articulations of the first metatarsal—medial cuneiform, navicular and talus. A relatively soft, resilient arch pad (e.g., sponge like material) that compresses as weight is applied may be permanently or removably attached atop the arch support 465. In one embodiment, the compressibility of the arch pad decreases the more the arch pad is compressed. By way of example, in such an embodiment, the bulk modulus of the pad may vary with the depth of the pad, from least at the exposed surface of the arch to greatest at the bottom. Removable attachments such as adhesives, snaps, hook and loop fasteners and other mechanical attachments may be utilized to secure the pad 465 to the arch support 460.

A cuneiform support structure 470 provides a mediolateral force to the medial cuneiform. This support structure provides both static and dynamic support functions.

A navicular relief structure 425 provides a mediolateral force to the medial navicular area. This support structure provides both static and dynamic support functions.

Various stiffening elements may added to enhance rigidity. For example, stiffener ribs and inserts may be utilized.

A method according to principles of the invention entails translating a downward force exerted by a foot during walking motion into pivotal motion of a medial support flange. Next, the pivotal motion the medial support flange urges the support flange against the medial cuneiform, navicular and talus areas of the foot. As the downward force is relieved, the medial support flange returns to its original position and the corresponding forces exerted against the medial cuneiform, navicular and talus areas of the foot are relieved. The process repeats as the gait cycle repeats.

A device 100 according to principles of the invention may be comprised of various materials, such as plastic. In an exemplary implementation, the orthotic device 100 is comprised of a plastic or polymeric material, such as polyvinyl chloride (PVC), polyethylene, polypropylene, polystyrene, acrylics, cellulosics, acrylonitrile-butadiene-styrene terpolymers, urethanes, thermo-plastic resins, thermo-plastic elastomers (TPE), acetal resins, polyamides, polycarbonates and polyesters. While many other materials may be used alone or in combination with the aforementioned materials and/or other materials, without departing from the scope of the present invention, preferably the material is relatively inexpensive, easy to use in manufacturing operations and results in an aesthetically acceptable, durable, weather resistant product. The material may further include additives to provide desired properties such as desired colors and structural characteristics.

The orthotic device 100 may be produced using any suitable manufacturing techniques known in the art for the chosen material, such as (for example) injection, compression, structural foam, blow, or transfer molding; polyurethane foam processing techniques; vacuum forming; and casting. For example, the device 100 may be produced as an integrally molded product, without the arch pad and heel cup, which can be over-molded or attached subsequently. Preferably, the manufacturing technique is suitable for mass production at relatively low cost per unit, and results in an aesthetically acceptable product with a consistent acceptable quality that withstands the stresses and environmental conditions encountered during use.

While an exemplary embodiment of the invention has been described, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. With respect to the above description then, it is to be realized that the optimum relationships for the components and steps of the invention, including variations in order, form, composition, function and manner of operation, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. The above description and drawings are illustrative of modifications that can be made without departing from the present invention, the scope of which is to be limited only by the following claims. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents are intended to fall within the scope of the invention as claimed. 

1. An orthotic device for a foot configured to provide static and dynamic stability, said device comprising: a base; a dynamic vertical support flange coupled to said base and configured to controllably pivot and apply pressure against corresponding medial areas of the foot; and and a means for controllably causing said dynamic vertical support flange to pivot.
 2. An orthotic device according to claim 1, said means for controllably causing said dynamic vertical support flange to pivot comprising a cantilever arch support pivotally coupled to said base and configured to pivot downwardly upon application of a downward force, said dynamic vertical support flange being operably coupled to said cantilever arch support and configured to pivot and apply pressure against corresponding medial areas of the foot when said cantilever arch support pivots downwardly.
 3. An orthotic device according to claim 1, said dynamic vertical support flange coupled to said cantilever arch support being configured to pivot and apply pressure against a medial arch and subtalar bone complex of the foot.
 4. An orthotic device according to claim 1, said dynamic vertical support flange including a support section configured to apply pressure to a portion of a foot from the group consisting of medial cuneiform, navicular and talar bone structures.
 5. An orthotic device according to claim 2, said cantilever arch support including an arch support pad configured to cushion an arch of the foot.
 6. An orthotic device according to claim 2, said cantilever arch support including a removably mounted arch support pad.
 7. An orthotic device according to claim 2, said cantilever arch support including an arch support pad and a recess in said cantilever arch support and coextensive with said arch support pad and configured to receive said arch support pad.
 8. An orthotic device according to claim 2, said cantilever arch support being arcuate and resilient.
 9. An orthotic device according to claim 1, further comprising a heel cup attached to said base, said heel cup being configured to support a heel of the foot.
 10. An orthotic device according to claim 1, further comprising a heel cup releasably attached to said base, said heel cup being configured to support a heel of the foot.
 11. An orthotic device according to claim 1, further comprising an integral heel cup tongue protruding rearwardly from the base, and a heel cup having a cavity configured to receive and engage the heel cup tongue.
 12. An orthotic device according to claim 1, further comprising an integral heel cup tongue protruding rearwardly from the base, said heel cup tongue including a locking protuberance, and a heel cup having a cavity configured to receive and engage the heel cup tongue, said heel cup including means for engaging said locking protuberance.
 13. An orthotic device according to claim 1, further comprising an integral heel cup tongue protruding rearwardly from the base, said heel cup tongue including a locking protuberance, and a removable heel cup having a cavity configured to receive and engage the heel cup tongue, said heel cup including means for releasably engaging said locking protuberance.
 14. An orthotic device according to claim 1, further comprising a removable sizing heel cup attached to said base, said heel cup being sized to cause the orthotic to fit the foot.
 15. An orthotic device according to claim 1, said base including at least one female receptacle, and said orthotic device further comprising a heel cup including at least one male prong configured to engage the at least one female receptacle and operably couple said heel cup to said base.
 16. An orthotic device according to claim 1, said base including at least one female receptacle, and said orthotic device further comprising an integral heel cup tongue protruding rearwardly from the base, said heel cup tongue including a locking protuberance, and a removable heel cup having a cavity configured to receive and engage the heel cup tongue, said heel cup including means for releasably engaging said locking protuberance, and said base including at least one female receptacle, and said heel cup including at least one male prong configured to engage the at least one female receptacle and operably couple said heel cup to said base.
 17. An integrally molded orthotic device for a foot configured to provide static and dynamic stability, said device comprising: a base; a dynamic vertical support flange coupled to said base and configured to controllably pivot and apply pressure against corresponding medial areas of the foot; and a cantilever arch support pivotally coupled to said base and configured to pivot downwardly upon application of a downward force, said dynamic vertical support flange being operably coupled to said cantilever arch support and configured to pivot and apply pressure against corresponding medial areas of the foot when said cantilever arch support pivots downwardly.
 18. An integrally molded orthotic device according to claim 17, further comprising means for attaching an arch support pad configured to cushion an arch of the foot.
 19. An integrally molded orthotic device according to claim 17, further comprising means for attaching a heel cup configured to cushion a heel of the foot.
 20. A method of stabilizing a medial arch and subtalar bone complex, said method comprising: translating a downward force exerted by a foot during walking motion into pivotal motion of a medial support flange; urging the medial support flange against corresponding areas of the foot to provide a stabilizing force; relieving the downward force; and relieving the stabilizing force as the downward force is relieved. 